U.S. patent number 11,165,532 [Application Number 16/346,024] was granted by the patent office on 2021-11-02 for controlling the impact of srs switching on uplink transmissions.
This patent grant is currently assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL). The grantee listed for this patent is TELEFONAKTIEBOLAGET LM ERICSSON (PUBL). Invention is credited to Muhammad Kazmi, Iana Siomina.
United States Patent |
11,165,532 |
Siomina , et al. |
November 2, 2021 |
Controlling the impact of SRS switching on uplink transmissions
Abstract
Methods and related nodes are disclosed that can enable the
control of the impact of SRS switching on uplink response
transmissions. In some aspects, the method comprises determining a
need to report measurements to a radio network node within a
measurement reporting delay, determining a need to perform an SRS
switching procedure, extending the measurement reporting delay
associated with reporting the measurements to the radio network
node in order to allow the UE to perform the SRS network node
within a measurement reporting delay.
Inventors: |
Siomina; Iana (Taby,
SE), Kazmi; Muhammad (Sundbyberg, SE) |
Applicant: |
Name |
City |
State |
Country |
Type |
TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) |
Stockholm |
N/A |
SE |
|
|
Assignee: |
TELEFONAKTIEBOLAGET LM ERICSSON
(PUBL) (Stockholm, SE)
|
Family
ID: |
1000005903816 |
Appl.
No.: |
16/346,024 |
Filed: |
November 2, 2017 |
PCT
Filed: |
November 02, 2017 |
PCT No.: |
PCT/IB2017/056835 |
371(c)(1),(2),(4) Date: |
April 29, 2019 |
PCT
Pub. No.: |
WO2018/083630 |
PCT
Pub. Date: |
May 11, 2018 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190245649 A1 |
Aug 8, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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62416411 |
Nov 2, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L
1/0026 (20130101); H04B 17/104 (20150115); H04W
24/10 (20130101); H04L 1/00 (20130101); H04W
72/1205 (20130101); H04B 17/309 (20150115) |
Current International
Class: |
H04L
1/00 (20060101); H04B 17/309 (20150101); H04B
17/10 (20150101); H04W 24/10 (20090101); H04W
72/12 (20090101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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Mar 2014 |
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2521292 |
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Mar 2014 |
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RU |
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2014 101 630 |
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Jul 2015 |
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RU |
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2008/131262 |
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Oct 2008 |
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WO |
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2011/093756 |
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Aug 2011 |
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WO |
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2011/103966 |
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WO |
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2012/154106 |
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WO |
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2017/173388 |
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Oct 2017 |
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WO |
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Other References
3GPP TSG RAN WG1 Meeting #86bis R1-1609985 Lisbon, Portugal Oct.
10-14, 2016 Agenda item: 7.2.5.3 Source: Qualcomm Incorporated
(Year: 2016). cited by examiner .
Qualcomm Incorporated: "Collision handling"; RI-1609985, 3GPP TSG
RAN WG1 Meeting #86bis, Lisbon, Portugal Oct. 10-14, 2016, 7 pages.
cited by applicant .
Huawei et al: "Discussion on SRS carrier based switching",
R4-162440, 3GPP TSG-RAN WG4 Meeting #78bis, San Jose del Cabo, MX,
Apr. 11-15, 2016, 3 pages. cited by applicant .
ISR and Written Opinion from corresponding application
PCT/IB2017/056835. cited by applicant .
Indian Office Action dated Oct. 22, 2020 issued in corresponding
Indian Application No. 201937016763, consisting of 6 pages. cited
by applicant .
European Examination Report dated Mar. 2, 2021 issued in
corresponding European Patent Application No. 17 804 664.5,
consisting of 5 pages. cited by applicant.
|
Primary Examiner: Khan; Mehmood B.
Attorney, Agent or Firm: Christopher & Weisberg,
P.A.
Parent Case Text
RELATED APPLICATIONS
The present application claims the benefits of priority of U.S.
Provisional Patent Application No. 62/416,411, entitled
"CONTROLLING THE IMPACT OF SRS SWITCHING ON UPLINK RESPONSE
TRANSMISSIONS", and filed at the United States Patent and Trademark
Office on Nov. 2, 2016, the content of which is incorporated herein
by reference.
Claims
What is claimed is:
1. A method in a user equipment, UE, the method comprising:
determining a need to report measurements to a radio network node
within a measurement reporting delay; while within the measurement
reporting delay, determining a need to perform a sounding reference
signal, SRS, carrier-based switching procedure to transmit SRS on
one or more different carriers; extending the measurement reporting
delay associated with reporting the measurements to the radio
network node in order to allow the UE to perform and complete the
SRS carrier-based switching procedure; and reporting the
measurements to the radio network node within the extended
measurement reporting delay.
2. The method as claimed in claim 1, further comprising performing
the measurements prior to determining a need to report measurements
to a radio network node within a measurement reporting delay.
3. The method as claimed in claim 1, wherein determining a need to
report measurements to a radio network node within a measurement
reporting delay is based, at least in part, on a measurement
configuration or on a measurement reporting configuration.
4. The method as claimed in claim 3, wherein the measurement
configuration or the measurement reporting configuration are
received from the radio network node.
5. The method as claimed in claim 1, wherein the measurements
comprise power measurements.
6. The method as claimed in claim 5, wherein the power measurements
comprise received signal strength measurements.
7. The method as claimed in claim 1, wherein the measurements
comprise quality measurements.
8. The method as claimed in claim 7, wherein the quality
measurements comprise received signal quality measurements.
9. The method as claimed in claim 1, wherein the measurements
comprise timing measurements.
10. The method as claimed in claim 9, wherein the timing
measurements comprise time of arrival measurements.
11. The method as claimed in claim 1, wherein the measurements are
event-triggered measurements.
12. The method as claimed in claim 1, wherein determining a need to
perform a SRS carrier-based switching procedure comprises receiving
a SRS request message from the radio network node or from another
radio network node.
13. A user equipment, UE, comprising processing circuitry, the
processing circuitry being configured to: determine a need to
report measurements to a radio network node within a measurement
reporting delay; while within the measurement reporting delay,
determine a need to perform a sounding reference signal, SRS,
carrier-based switching procedure; extend the measurement reporting
delay associated with reporting the measurements to the radio
network node in order to allow the UE to perform and complete the
SRS carrier-based switching procedure; and report the measurements
to the radio network node within the extended measurement reporting
delay.
14. The UE as claimed in claim 13, wherein the processing circuitry
is further configured to perform the measurements prior to
determining a need to report measurements to a radio network node
within a measurement reporting delay.
15. The UE as claimed in claim 13, wherein determining a need to
report measurements to a radio network node within a measurement
reporting delay is based, at least in part, on a measurement
configuration or on a measurement reporting configuration.
16. The UE as claimed in claim 15, wherein the processing circuitry
is further configured to receive the measurement configuration or
the measurement reporting configuration from the radio network
node.
17. The UE as claimed in claim 13, wherein the measurements
comprise power measurements.
18. The UE as claimed in claim 17, wherein the power measurements
comprise received signal strength measurements.
19. The UE as claimed in claim 13, wherein the measurements
comprise quality measurements.
20. The UE as claimed in claim 19, wherein the quality measurements
comprise received signal quality measurements.
21. The UE as claimed in any one of claim 13, wherein the
measurements comprise timing measurements.
22. The UE as claimed in claim 21, wherein the timing measurements
comprise time of arrival measurements.
23. The UE as claimed in claim 13, wherein the measurements are
event-triggered measurements.
24. The UE as claimed in claim 13, wherein when determining a need
to perform a SRS carrier-based switching procedure, the processing
circuitry is further configured to receive a SRS request message
from the radio network node or from another radio network node.
Description
TECHNICAL FIELD
The present description generally relates to wireless
communications and wireless communication networks, and more
particularly relates to reference signals and reference signaling
in wireless communication networks.
BACKGROUND
Sounding Reference Signals
Sounding reference signals (SRS) are known signals that are
transmitted by user equipments (UEs), e.g., to allow the base
station or eNodeB to estimate different uplink channel properties.
These estimates may be used for uplink scheduling and link
adaptation but also for downlink multiple antenna transmission,
especially in case of TDD where the uplink and downlink use the
same frequencies. The SRS are shown in FIG. 1 and generally have a
time duration of a single OFDM symbol.
SRS can be transmitted in the last symbol of a 1 ms uplink
subframe, and for the case with TDD, the SRS can also be
transmitted in the special slot UpPTS. The length of UpPTS can be
configured to be one or two symbols. In FIG. 2, an example is given
for TDD with 3 downlink (DL) subframes and 2 uplink (UL) subframe.
Generally, within a 10 ms radio frame, up to eight symbols may be
set aside for sounding reference signals (SRS).
The configuration of SRS symbols, such as SRS bandwidth, SRS
frequency domain position, SRS hopping pattern, and SRS subframe
configuration are usually set semi-statically as a part of RRC
information element.
There are two types of SRS transmissions in LTE UL: 1) periodic SRS
transmissions, and 2) aperiodic SRS transmissions. Periodic SRS is
transmitted at regular time instances as configured by means of RRC
signaling. Aperiodic SRS is a one-shot transmission that is
triggered by signaling in PDCCH.
There are two different configurations related to SRS: 1) Cell
specific SRS configuration, and 2) UE specific configuration. The
cell specific configuration indicates what subframes may be used
for SRS transmissions within the cell as illustrated, for instance,
in FIG. 2. The UE specific configuration indicates to the UE a
pattern of subframes (among the subframes reserved for SRS
transmission within the cell) and frequency domain resources to be
used for SRS transmission of that specific UE. It also includes
other parameters that the UE can use when transmitting the signal,
such as frequency domain comb and cyclic shift.
This means that sounding reference signals from different UEs can
be multiplexed in the time domain, by using UE-specific
configurations such that the SRS of two UEs are transmitted in
different subframes. Furthermore, within the same symbol, sounding
reference signals can be multiplexed in the frequency domain. The
set of subcarriers is divided into two sets of subcarriers, or
combs with the even and odd subcarriers respectively in each such
set. Additionally, UEs may have different bandwidths to get
additional FDM (The comb enables frequency domain multiplexing, or
FDM, of signals with different bandwidths and also overlapping.).
Additionally, code division multiplexing can be used. In such
cases, different UEs can use exactly the same time and frequency
domain resources by using different shifts of a basic base
sequence.
SRS Carrier Based Switching
In LTE networks, there are many kinds of downlink heavy traffic,
which leads to a larger number of aggregated downlink component
carriers (CCs) than the number of (aggregated) uplink CCs. For the
existing UE categories, the typical carrier aggregation (CA)
capable UEs only support one or two uplink CCs while up to 5 CCs
can be aggregated in downlink.
Some of the TDD carriers with downlink transmissions for the UE may
have no uplink transmission(s) including SRS, and channel
reciprocity cannot be used for these carriers. Such situations will
become more severe with CA enhancement of up to 32 CCs where a
large portion of the CCs are TDD. Allowing fast carrier switching
to and between TDD uplink carriers can be a solution to allow SRS
transmission on these TDD carriers.
SRS based carrier switching is aiming to support SRS switching to
and between TDD component carrier(s), where the component carriers
available for SRS transmission correspond to the component carriers
available for carrier aggregation of PDSCH, while the UE has fewer
component carriers available for carrier aggregation of PUSCH.
SRS based carrier switching simply means that during certain time
resources the UE does not transmit any signal on one carrier (e.g.
F1) while it transmits SRS on another carrier (e.g. F2). For
example, F1 and F2 can be PCell and SCell respectively, or both can
be SCells.
CA-Related Interruptions in LTE
The current CA-related interruption requirements are specified in
36.133, v13.3.0, e.g., as below.
======<<<<<<TS
36.133>>>>>======
7.8.2.3 Interruptions at SCell activation/deactivation for
intra-band CA
When an intra-band SCell is activated or deactivated as defined in
[2] the UE is allowed an interruption of up to 5 subframes on PCell
during the activation/deactivation delay defined in Section 7.7.
This interruption is for both uplink and downlink of PCell.
7.8.2.4 Interruptions at SCell activation/deactivation for
inter-band CA
When an inter-band SCell is activated or deactivated as defined in
[2] the UE that requires interruption is allowed an interruption of
up to 1 subframe on PCell during the activation/deactivation delay
defined in Section 7.7. This interruption is for both uplink and
downlink of PCell.
======<<<<<<TS
36.133>>>>>======
Similar interruptions may occur also due to SRS switching.
UL Response Transmissions
ACK/KNACK Feedback
ACK/NACK feedback is used, e.g., in LTE, by the intended receiving
node to inform a transmitting node that its transmission has been
or has not been successfully received. The ACK/NACKs may be
transmitted in response to downlink or uplink transmissions by UE
(via uplink control channel or data channel) or base station or eNB
(via the PHICH), respectively. For HARQ feedback (i.e. ACK or NACK)
transmitted by the UE in uplink, it is in general expected that in
FDD the UE transmits the feedback in subframe n+4 for the downlink
reception in subframe n. For TDD, the relation is also pre-defined
but depends on the TDD configuration. In HD-FDD, the timing
relation between reception of data at the UE and transmission of
HARQ feedback (i.e. ACK or NACK) in the uplink is also pre-defined
e.g. in NB-IoT, the ACK/NACK is sent in subframe n+12.
CSI Feedback
Channel state information (CSI) feedback is used to deliver the
information for eNBs about downlink channel state. CSI may be of
different types: CQI, PMI, RI, and PTI, which may also be viewed as
a special type of radio measurements.
Radio Measurement Reporting
UE receives radio signals/channels in downlink, performs one or
more radio measurements, and reports one or more results of the
radio measurements. Some radio measurement examples are RSRP/RSRQ,
CSI (including CQI, PMI, RI, PTI), timing measurements, or even CGI
reading or SI (system information) reading. In addition to
measurement time (a.k.a. measurement period) requirements, there
may also be measurement reporting delay requirements.
Bidirectional Measurements
The radio measurements can be unidirectional or bidirectional.
Examples of bidirectional measurements are Rx-Tx (e.g., UE Rx-Tx,
eNB Rx-Tx), timing advance type 1 and timing advance type 2 (see
3GPP 36.214), round trip time (RTT), etc. For example, with UE
Rx-Tx, the UE upon receiving radio signals (CRS) in downlink
transmits an uplink transmission (SRS or RACH), which may also be
viewed as a type of UL response transmissions.
UL Transmission Based on Scheduling or Trigger Received in DL
The UE may be required to transmit (e.g., a physical signal or a
physical channel or data via higher layers) or provide some
information within a certain time or with at most some maximum
delay upon receiving in downlink a transmission request or a
trigger or scheduling information. Herein, such transmissions may
also be viewed as UL response transmissions.
Pre-Defined Acknowledgement of a UE Operation
For example, upon activating a CC, the UE should report
corresponding valid CSI for the activated SCell on the next
available uplink reporting resource after receiving the reference
signal. In another example, with dual connectivity, upon receiving
PSCell addition in subframe n, the UE should be capable to transmit
a PRACH preamble towards the PSCell no later than in subframe
n+T.sub.config_PSCell (as specified in 3GPP TS 36.133).
SUMMARY
SRS carrier based switching and related transmissions (e.g., SRS
and PRACH) may impact UL transmissions (e.g., UL response
transmissions), which may not be possible to transmit in time.
Therefore, new mechanisms are needed to control the impact of SRS
switching on UL transmissions.
According to a broad aspect, the UE adapts its SRS carrier based
switching configuration and/or associated transmissions (e.g., SRS
or PRACH) and/or its UL transmissions in order to control (e.g.,
avoid, reduce, or minimize) the impact of SRS carrier based
switching (e.g., interruption impact or the impact of sharing the
transmitter or other UE resources) on UL transmissions. The
adaptation is used to maintain UE performance and/or ensure that
the UE is able to meet corresponding requirements.
According to one aspect, some embodiments include a method
implemented in a UE, the method comprises determining a need to
report measurements to a radio network node within a measurement
reporting delay, determining a need to perform a sounding reference
signal, SRS, switching procedure, extending the measurement
reporting delay associated with reporting the measurements to the
radio network node in order to allow the UE to perform the SRS
switching procedure, and reporting the measurements to the radio
network node within the extended measurement reporting delay.
In some embodiments, the method may comprise, or further comprise,
performing the measurements prior to determining the need to report
measurements to the radio network node within the measurement
reporting delay.
In some embodiments, determining a need to report measurements to a
radio network node within a measurement reporting delay may be
based, at least in part, on a measurement configuration or on a
measurement reporting configuration. In such embodiments, the
measurement configuration or the measurement reporting
configuration may be received from the radio network node.
In some embodiments, the measurements may comprise power
measurements. In such embodiments, the power measurements may
comprise received signal strength measurements. In such
embodiments, the power measurements may comprise, or further
comprise, Reference Signal Received Power (RSRP) measurements.
In some embodiments, the measurements may comprise quality
measurements. In such embodiments, the quality measurements may
comprise received signal quality measurements. In such embodiments,
the quality measurements may comprise, or further comprise,
Reference Signal Received Quality (RSRQ) measurements.
In some embodiments, the measurements may comprise timing
measurements. In such embodiments, the timing measurements may
comprise different time measurements. In such embodiments, the
timing measurements may comprise, or further comprise, Rx-Tx
measurements, or Round-Trip-Time (RTT) measurements, or Reference
Signal Time Difference (RSTD) measurements, or Time of Arrival
(TOA) measurements, or Time Difference of Arrival (TDOA)
measurements.
In some embodiments, the measurements may be event-triggered
measurements.
In some embodiments, determining a need to perform a SRS switching
procedure may comprise receiving a SRS request message from the
radio network node or from another radio network node.
According to another aspect, some embodiments include a UE
configured, or operable, to perform one or more UE functionalities
(e.g. steps, actions, etc.) as described herein.
In some embodiments, the UE may comprise a communication interface
configured to communicate with one or more radio nodes and/or with
one or more network nodes, and processing circuitry operatively
connected to the communication interface, the processing circuitry
being configured to perform one or more UE functionalities as
described herein. In some embodiments, the processing circuitry may
comprise at least one processor and at least one memory storing
instructions which, upon being executed by the processor, configure
the processor to perform one or more UE functionalities as
described herein.
In some embodiments, the UE may comprise one or more functional
modules configured to perform one or more UE functionalities as
described herein.
According to another aspect, some embodiments include a computer
program product comprising a non-transitory computer readable
storage medium storing computer readable program instructions or
code which, upon being executed by processing circuitry (e.g., a
processor) of the UE, configure the processing circuitry to perform
one or more UE functionalities as described herein.
Some embodiments may enable the quality of UE UL transmissions to
be maintained even when the UE is performing SRS switching.
This summary is not an extensive overview of all contemplated
embodiments, and is not intended to identify key or critical
aspects or features of any or all embodiments or to delineate the
scope of any or all embodiments. In that sense, other aspects and
features will become apparent to those ordinarily skilled in the
art upon review of the following description of specific
embodiments in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments will be described in more detail with
reference to the following figures, in which:
FIG. 1 is a diagram of an uplink subframe in which SRS can be
transmitted in accordance with some embodiments.
FIG. 2 is a diagram of an example of downlink and uplink subframes
configuration in TDD.
FIG. 3 is a schematic diagram of an example wireless communication
network in accordance with some embodiments.
FIG. 4 is a schematic diagram of an example of SRS carrier based
switching.
FIG. 5 is a flow chart of operations of a user equipment (UE) in
accordance with some embodiments.
FIG. 6 is another flow chart of operations of a user equipment (UE)
in accordance with some embodiments.
FIG. 7 is a flow chart of operations of a radio network node in
accordance with some embodiments.
FIG. 8 is a block diagram of a user equipment (UE) in accordance
with some embodiments.
FIG. 9 is a block diagram of a radio network node in accordance
with some embodiments.
FIG. 10 is another block diagram of a user equipment (UE) in
accordance with some embodiments.
FIG. 11 is another block diagram of a radio network node in
accordance with some embodiments.
DETAILED DESCRIPTION
The embodiments set forth below represent information to enable
those skilled in the art to practice the embodiments. Upon reading
the following description in light of the accompanying figures,
those skilled in the art will understand the concepts of the
description and will recognize applications of these concepts not
particularly addressed herein. It should be understood that these
concepts and applications fall within the scope of the
description.
In the following description, numerous specific details are set
forth. However, it is understood that embodiments may be practiced
without these specific details. In other instances, well-known
circuits, structures, and techniques have not been shown in detail
in order not to obscure the understanding of the description. Those
of ordinary skill in the art, with the included description, will
be able to implement appropriate functionality without undue
experimentation.
References in the specification to "one embodiment," "an
embodiment," "an example embodiment," etc., indicate that the
embodiment described may include a particular feature, structure,
or characteristic, but every embodiment may not necessarily include
the particular feature, structure, or characteristic. Moreover,
such phrases are not necessarily referring to the same embodiment.
Further, when a particular feature, structure, or characteristic is
described in connection with an embodiment, it is submitted that it
is within the knowledge of one skilled in the art to implement such
feature, structure, or characteristic in connection with other
embodiments whether or not explicitly described.
As used herein, the singular forms "a", "an" and "the" are intended
to include the plural forms as well, unless the context clearly
indicates otherwise. It will be further understood that the terms
"comprises," "comprising," "includes," and/or "including" when used
herein, specify the presence of stated features, integers, steps,
operations, elements, and/or components, but do not preclude the
presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof.
FIG. 3 illustrates an example of a wireless network 100 that may be
used for wireless communications. Wireless network 100 includes UEs
110A-110B and a plurality of radio network nodes 130A-130B (e.g.,
eNBs, gNBs, etc.) connected to one or more core network nodes 150
via an interconnecting network 125. The network 100 may use any
suitable deployment scenarios. UEs 110 within coverage areas 115A
and 115B may each be capable of communicating directly with radio
network nodes 130 over a wireless interface. In certain
embodiments, UEs may also be capable of communicating with each
other via device-to-device (D2D) communication.
As an example, UE 110A may communicate with radio network node 130A
over a wireless interface. That is, UE 110A may transmit wireless
signals to and/or receive wireless signals from radio network node
130A. The wireless signals may contain voice traffic, data traffic,
control signals, and/or any other suitable information. In some
embodiments, an area of wireless signal coverage associated with a
radio network node 130 may be referred to as a cell.
In some embodiments, a more general term "network node" is used and
can correspond to any type of radio network node (or radio access
node) or any network node, which can communicate with a UE and/or
with another network node in a cellular, mobile, and/or wireless
communication system. Examples of network nodes are NodeB, eNB,
MeNB, SeNB, a network node belonging to MCG or SCG, base station
(BS), multi-standard radio (MSR) radio network node such as MSR BS,
network controller, radio network controller (RNC), base station
controller (BSC), relay, donor node controlling relay, base
transceiver station (BTS), access point (AP), transmission points,
transmission nodes, RRU, RRH, nodes in distributed antenna system
(DAS), core network node (e.g. MSC, MME, etc.), O&M, OSS, SON,
positioning node (e.g. E-SMLC), MDT, test equipment, etc. Example
embodiments of a network node are described in more detail below
with respect to FIG. 9.
In some embodiments, the terms "user equipment" or "UE" may be used
herein to refer to any type of wireless device communicating with a
network node and/or with another UE in a cellular, mobile, and/or
wireless communication system. Examples of UE are target device,
device to device (D2D) UE, machine type UE or UE capable of machine
to machine (M2M) communication, personal digital assistant (PDA),
tablet, mobile terminal, smart phone, laptop embedded equipped
(LEE), laptop mounted equipment (LME), USB dongles etc. Example
embodiments of a UE are described in more detail below with respect
to FIG. 8.
In the description, any of the above-mentioned nodes, including UE,
network node, and radio network node, can be "the first node"
and/or "the second node" in the embodiments described herein. In
some embodiments, the first node and the second node may be capable
of at least one of transmitting and receiving in licensed and/or
unlicensed spectrum.
In some embodiments, the terms "radio access technology" or "RAT"
may refer to any RAT, e.g., UTRA, E-UTRA, narrow band internet of
things (NB-IoT), Wi-Fi, Bluetooth, next generation RAT (NR), 4G,
5G, etc. Any of the first and the second nodes may be capable of
supporting a single or multiple RATs.
A UE may be configured to operate in carrier aggregation (CA)
implying aggregation of two or more carriers in at least one of DL
and UL directions. With CA, a UE can have multiple serving cells,
wherein the term "serving" herein means that the UE is configured
with the corresponding serving cell and may receive from and/or
transmit data to the network node on the serving cell e.g. on PCell
or any of the SCells. The data is transmitted or received via
physical channels e.g. PDSCH in DL, PUSCH in UL, etc. A component
carrier (CC) also interchangeably called as carrier or aggregated
carrier, PCC or SCC, is configured at the UE by the network node
using higher layer signaling e.g. by sending RRC configuration
message(s) to the UE. The configured CC is used by the network node
for serving the UE on the serving cell (e.g. on PCell, PSCell,
SCell, etc.) of the configured CC. The configured CC is also used
by the UE for performing one or more radio measurements (e.g. RSRP,
RSRQ, etc.) on the cells operating on the CC e.g. PCell, SCell, or
PSCell, and neighboring cells.
In some embodiments, the terms "dual connectivity" or "DC" used
herein may refer to the operation mode wherein the UE can be served
by at least two nodes called master eNB (MeNB) and secondary eNB
(SeNB). More generally, in multiple connectivity (also referred to
as multi-connectivity) operation, the UE can be served by two or
more nodes e.g. MeNB, SeNB1, SeNB2, and so on. The UE is configured
with PCC from both MeNB and SeNB. The PCell from MeNB and SeNB are
called as PCell and PSCell respectively. The PCell and PSCell
operate the UE typically independently. The UE can also be
configured with one or more SCCs from each of MeNB and SeNB. The
corresponding secondary serving cells served by MeNB and SeNB are
called SCell. The UE in DC typically has separate transceivers for
each of the connections with MeNB and SeNB. This allows the MeNB
and SeNB to independently configure the UE with one or more
procedures e.g. radio link monitoring (RLM), DRX cycle, etc., on
their PCell and PSCell respectively.
In some embodiments, the term "SRS" used herein may refer to any
type of reference signal (RS) or more generally physical radio
signals transmitted by the UE in the UL to enable the network node
to determine the UL signal quality, e.g. UL SNR, UL SINR, etc.
Examples of such reference signals are sounding reference signals,
DMRS, UE specific reference or pilot signals, etc. The embodiments
are applicable to any type of RS i.e. switching of carrier
transmitting any type of RS.
In some embodiments, the term "signal" used herein can be any
physical signal, including, but not limited to, reference signal
such as PSS, SSS, CRS, PRS, etc.
In some embodiments, the term "channel" (e.g., in the context of
channel reception) used herein can be any physical channel,
including, but not limited to, MIB, PBCH, NPBCH, PDCCH, PDSCH,
MPDCCH, NPDCCH, NPDSCH, E-PDCCH, PUSCH, PUCCH, NPUSCH, etc.
In some embodiments, the term "time resource" used herein may
correspond to any type of physical resource or radio resource
expressed in terms of length of time. Examples of time resources
include symbol, time slot, subframe, radio frame, TTI, interleaving
time, etc.
In some embodiments, the term "radio measurement" used herein may
comprise any measurement based on receiving a radio signal or
channel, e.g., power-based measurements such as received signal
strength (e.g., RSRP or CSI-RSRP) or quality measurements (e.g.,
RSRQ, RS-SINR, SINR, Es/Iot, SNR); cell identification;
synchronization signals measurements; angle measurements such as
angle of arrival (AOA); timing measurements such as Rx-Tx, RTT,
RSTD, TOA, TDOA, timing advance; throughput measurements; channel
quality measurements such CSI, CQI, PMI. A measurement may be
absolute, relative to a common reference or to another measurement,
composite measurement, etc. A measurement may be on one link or
more than one links (e.g., RSTD, timing advance, RTT, relative
RSRP; etc.). Measurements may also be differentiated by purpose and
may be performed for one or more purposes, e.g., for one or more
of: RRM, MDT, SON, positioning, timing control or timing advance,
synchronization.
Herein, the term "radio measurement" may be used in a broader
sense, e.g., receiving a channel (e.g., receiving system
information via broadcast or multicast channel).
In some embodiments, the term "requirements" used herein may
comprise any type of UE requirements related to UE measurements,
also referred to as measurement requirements, RRM requirements,
mobility requirements, positioning measurement requirements, etc.
Examples of UE requirements related to UE measurements include
measurement time, measurement reporting time or delay, measurement
accuracy (e.g. RSRP/RSRQ accuracy), number of cells to be measured
over the measurement time, etc. Examples of measurement time are L1
measurement period, cell identification time or cell search delay,
CGI acquisition delay, etc.
In some embodiments, SRS switching and SRS carrier based switching
may be used interchangeably to describe transmitting SRS on
different carriers. SRS switching may be based on a time and/or
frequency domain pattern.
In some embodiments, the term "UL response transmission" may
comprise, e.g., UE measurement report, CSI feedback, UE ACK/NACK
transmission, UE transmission comprising one of the two measurement
components of a bidirectional measurement, UE transmission in
response a signal/channel/message received in DL, pre-defined
acknowledgement of completing a UE operation (e.g., CC
(de)activation or PSCell addition/release), etc.
A broad exemplary scenario comprises of a UE being served by a
first network node with a PCell operating on a first carrier
frequency (f1), wherein the UE is also capable of being served by
at least one secondary serving cell (SCell) also known as a first
SCell. The UE may further be capable of being served by two or more
SCells, e.g., the first SCell operates on a second carrier
frequency (f2) and the second SCell operates on a third carrier
frequency (f3). The same applies for more than two SCells. The
carrier frequency f1 is interchangeably called as PCC, while
carrier frequencies f2, f3, . . . f(n) may interchangeably be
called as SCC1, SCC2, SCC(n-1), etc., respectively.
In one example, all f1, f2, and f3 belong to a licensed spectrum.
In yet another example, carriers f1 and f3 may belong to a licensed
spectrum or frequency band, whereas f2 may belong to an unlicensed
spectrum or frequency band. Other combinations are also possible.
In an unlicensed spectrum or band, contention based transmission is
allowed i.e. two or more devices (UE or network nodes) can access
even the same part of spectrum based on certain fairness
constraints, e.g. LBT. In this case, no operator (or user or
transmitter) owns the spectrum. In a licensed spectrum or licensed
band, only contention free transmission is allowed i.e. only
devices (UE or network nodes) allowed by the owner of the spectrum
license can access the licensed spectrum. In one example of the use
case, all carriers can be in unlicensed spectrum, or in a licensed
shared spectrum or in a spectrum where LBT is required.
In one example, the CCs and the corresponding serving cells of a UE
may be comprised all in the same node. In another example, at least
two of them may be comprised in different nodes, which may be
co-located or non-collocated.
In one example, all the CCs and the corresponding serving cells of
a UE may be configured in the same timing advance group (TAG) e.g.
pTAG. In another example, some CCs and the corresponding serving
cells of a UE may be configured in one timing advance group (TAG)
(e.g. pTAG) and remaining CCs in another TAG (e.g. sTAG). In yet
another example, the UE may be configured with 2 or more TAGs.
The above scenarios may also comprise DC or multi-connectivity
operations performed based on corresponding CA configurations,
where PSCell in different embodiments may be belong, e.g., to a set
of SCells.
SRS switching may involve at least one of: starting SRS
transmission on a first carrier frequency and/or stopping SRS
transmission on a second carrier frequency, wherein the first and
the second carrier frequency may belong to licensed and/or
unlicensed spectrum, same RAT or different RATs. According to the
earlier examples, the SRS carrier based switching may involve any
one or more carriers of f1, f2, f3, . . . f(n); starting and/or
stopping SRS transmission from one or more antennas or antenna
ports.
In one example, SRS switching may comprise carrier based SRS
switching and/or antenna based SRS switching.
The SRS switching may be controlled by the network and/or by the
UE.
Even though some embodiments are described for carrier based SRS
switching, they are applicable for any SRS switching type.
Switching among carriers and/or antennas during SRS switching may
cause some interruptions, e.g., to PCell or activated SCell, which
may be due to UE reconfiguration such as configuring and/or
activating target carriers (to which the SRS transmission is
switched to), deconfiguring and/or deactivating source carriers
(from which SRS transmission is switched), delays, reduced
performance, etc.
As an exemplary CC combination shown in FIG. 4, there is a CA
arrangement with 5 DL component carriers and 2 UL component
carriers. In this example, one UL component carrier is fixed in the
PCell and the SRS switching is done on one of the SCells (e.g.,
from SCell 1 to SCell2). So, at any point of time, it is a 2 UL
component carriers combination. The same example scenario can also
be shown with other numbers aggregated CCs in DL and UL
respectively. The carriers, i.e. CCy, CCz, CCu and CCv, can be in
different band also. For example, CCy can be in any band below 1
GHz, CCz can be in any band around 2 GHz, and CCu can be any band
in 3.5 GHz.
The term "served" or "being served" herein means that the UE is
configured with the corresponding serving cell and can receive from
and/or transmit data to the network node on the serving cell e.g.
on PCell or any of the SCells. The data is transmitted or received
via physical channels e.g. PDSCH in DL, PUSCH in UL, etc.
The UE may be requested to switch SRS transmission to one or more
serving cells by the network node. In some embodiments one or more
SRS switching messages or commands may be received by the UE, e.g.,
via RRC signaling, via MAC CE command, or via a physical layer
message (e.g., downlink control information (DCI) carried by a
PDCCH), etc.
For example, the following signaling may apply: Receiving a first
serving cell SRS switching request message or command from a second
network node for switching SRS carrier from the first serving cell;
Receiving a second serving cell SRS switching request message or
command from a third network node for switching SRS carrier from
the second serving cell; Receiving a third serving cell SRS
switching request message or command from a fourth network node for
switching SRS carrier from the third serving cell.
In some embodiments, at least some of the first, second, third and
fourth network nodes are the same or are co-located at the same
site or location. For example, in such embodiments, the UE may
receive one or more messages or command for switching SRS
carrier(s) from one or more serving cells from the first network
node. Also, for example in such embodiments, the UE may receive one
or more messages for SRS switching of one or more serving cells
from the PCell.
In some embodiments, any combination of the first, second, third
and fourth network nodes are different and may be located at
different sites or location or may be logically different nodes
that may still be co-located. In such embodiments, the UE may
receive one or more messages for SRS carrier switching from one or
more serving cells from the respective serving cells.
FIG. 5 illustrates an embodiment of a method which can be performed
in a UE such as UE 110. The method may comprise:
Step S100 (Optional): Sending a message or indicating to another
node (e.g., a network node or another UE) indicative of the UE's
ability to adapt its operations with SRS switching in order to
control (e.g., avoid, reduce, or minimize) the impact of SRS
switching on UL response transmissions.
Step S102: Determining that the UE may need to perform one or more
UL response transmissions on a first carrier frequency (F1) in a
first set of time resources (R1).
Step S104: Determining that the UE may need to perform SRS
switching and associated transmissions (e.g., SRS and/or PRACH) on
at least a second cell (cell2) operating on a second carrier
frequency (F2)
Step S106: Adaptively performing UE's operations with SRS
switching, based on the determined R1.
Step S108: Using the result of the adaptation for one or more
operational tasks and/or sending the result to another node.
It will be appreciated that one or more of the above steps may be
performed simultaneously and/or in a different order. Also, steps
illustrated in dashed lines are optional and may be omitted in some
embodiments.
The steps will now be described in more detail.
Step S100
In this step, the UE may send a message or indicate to another node
(e.g., a network node or another UE) the UE's ability to adapt its
operations with SRS switching in order to control (e.g., avoid,
reduce, or minimize) the impact of SRS switching on UL response
transmissions.
The impact of SRS switching may comprise, e.g., interruptions
impact, additional delays e.g. due to switching,
dropping/deprioritizing some UL transmissions (UL response
transmissions or SRS switching related transmissions) due to limits
imposed by UE uplink carrier aggregation capability, etc.
The indication may also comprise the UE's ability to operate
according to one or more embodiments described herein.
The capability may be signaled, e.g., upon a request from another
node or upon a triggering condition or event or receiving a certain
message from another node.
Step S102
In this step, the UE may determine that it may need to perform one
or more UL response transmissions on a first carrier frequency (F1)
in a first set of time resources (R1).
In some embodiments, the UL response transmissions may be
transmitted in response to receiving one or more radio signals on
F1 in another set of time resources (R1*). The UE may determine R1
based on the determined R1*.
The need to perform one or more UL response transmissions may be
determined, e.g., based on one or more of: Pre-defined rule or
requirement (e.g., the UE is expected to transmit not later than
after time T or in a specific time resource n+k if the DL reception
was received in time resource n); Measurement configuration;
Measurement reporting configuration; Trigger or message (e.g.,
unicast/multicast/broadcast) received from another node and the
associated time resources R1*; Specific signal or channel received
from another node and the associated time resources R1*; Scheduling
grant and associated time resources R1*; Timer or counter (e.g.,
for periodic reporting); Completing an operation (e.g., CC
activation); Specific set of resources R are dedicated or scheduled
for critical UL response transmissions (and thus the resources may
need to be protected from the impact of SRS switching, even if it
is not known in advance whether the transmission will happen, e.g.,
the UE may not get access to the channel requiring CSMA-like or
listening-based or LBT-based channel access prior actually
transmitting a configured UL transmission); UL resources used for a
bidirectional measurement, e.g., UE Rx-Tx; UE activity state (e.g.,
the UE may not transmit at least certain transmissions in UL during
a configured DRX inactive state).
Step S104
In this step, the UE may determine the need to perform SRS
switching and associated transmissions (e.g., SRS and/or PRACH) on
at least a second cell (cell2) operating on a second carrier
frequency (F2).
The determining may be based, e.g., on: UE activity state (e.g.,
SRS switching only in non-DRX state or short DRX state, but not in
eDRX or not in DRX); SRS switching type; SRS switching
configuration; A message, a trigger or an indication indicative of
the need to perform the SRS carrier based switching, received from
a higher layer in the first node or from another node (e.g., a
network node or another UE); An event, a condition, or a trigger
according to which the SRS carrier based switching needs to be
performed; A timer in the first node indicating that the SRS
carrier based switching needs to be performed (e.g., for periodic
or scheduled measurements); A time- and/or frequency-domain pattern
controlling when the SRS carrier based switching is to be performed
and which frequency resources (e.g., carriers) are involved; SRS
(re)configuration for the SRS transmissions to start in relation to
the SRS carrier based switching; SRS (re)configuration for the SRS
transmissions to stop in relation to the SRS carrier based
switching.
Step S106
In this step, the UE may adaptively perform UE's operations with
SRS switching, based on the determined R1.
The adaptation may comprise, e.g., adapting one or more of: SRS
switching configuration; transmission(s) associated with SRS
switching (e.g., SRS transmissions and/or PRACH transmissions); UL
response transmission(s).
The adaptation may further comprise, e.g., any one or more of:
Adapting based on relative priority(-ies) for the procedures or
performance of SRS switching and/or its associated transmissions
and UL response transmissions; Adapting a configuration parameter
for SRS switching; Adapting a configuration parameter for
transmission related to SRS switching (e.g., SRS transmission
configuration parameters; PRACH transmission configuration
parameters: configuration index, time resources, preamble format,
subcarrier spacing, transmit power, etc.); Adapting a configuration
parameter for UL response transmission(s) (e.g., scheduling or time
and/or frequency resources, transmit power, bandwidth, format,
number of retransmissions, UL response transmission delay or time
period e.g. delay for measurement reporting in UL);
Dropping/skipping/postponing/delaying/performing earlier/resuming
SRS switching and/or SRS transmission;
Dropping/skipping/postponing/delaying/performing
earlier/resuming/retransmitting/rescheduling UL response
transmission(s);
Postponing/delaying/resuming/retransmitting/rescheduling UL
response transmission(s) with certain delay e.g. after L1 number
time resources; Aborting the UL response transmission if it cannot
be delivered after L2 number of interruptions due to SRS switching;
Transmitting UL response transmission on a carrier different from F
1 instead of transmitting on F1; Misaligning in time (e.g., by
adapting periodicity, scheduling in time, any of the above, etc.)
of the resources R2 on F1 affected by SRS switching and related
PRACH/SRS transmissions and the resources R1 for the UL response
transmission, e.g., allowing at least time T or N time resources
between R2 and R1 (in a special case, T and N can be zero, i.e.
adjacent R2 and R1); Ensuring that no more than X of R1 resources
overlap with R2; Ensuring that no more than X % of R1 resources
overlap with R2; Ensuring that no more than Y % of R2 resources
overlap with R1; Ensuring that the total amount of interruption
impact on cell1 (including the interruptions due to SRS switching)
is below a threshold or the interruption probability does not
exceed a threshold; Increasing the number of UL response
transmission attempts if at least some overlap of R1 and R2 occurs;
Increasing reliability or robustness (e.g., adapting MCS and/or Tx
power) of other UL response transmission attempts to compensate for
the reduced number of transmission attempts due to the SRs
switching impact; Increasing the measurement period of a
bidirectional measurement if one or more of its UL components
(comprising UL response transmission) may be impacted by the SRS
switching or related SRS transmission; Reducing the transmit power
of one or both of SRS transmission and UL response transmission to
ensure that the sum transmit power does not exceed a threshold or
the UE transmission capability.
The adapted configuration(s) of SRS switching, SRS transmission(s)
and/or UL response transmission(s) may be obtained based, e.g., on
a pre-defined rule, requirement, table, message or indication
received from another node, etc.
The adaption is performed in order to control (e.g., avoid, reduce,
or minimize) the impact of SRS carrier based switching (e.g.,
interruption impact or the impact of sharing the transmitter or
other UE resources) on UL response transmissions. The adaptation is
used to maintain UE performance and/or ensure that the UE is able
to meet corresponding requirements.
SRS switching configuration may comprise, e.g., one or more of: SRS
switching period (i.e., time after which the UE switch to another
carrier to transmit SRS); Number or a set of carriers involved in
SRS carrier based switching; Sequence in which the carriers are
switched; SRS switching loop length (e.g., the time to the next
transmission on the same carrier); SRS transmission configuration
(see e.g. SRS transmission parameters as described in the
background); PRACH transmission configuration; Time-to-stay on the
carrier during SRS carrier based switching; Minimum or maximum time
before SRS transmission on the SRS switching target carrier
frequency; Minimum or maximum time after the SRS transmission on
the SRS switching source carrier frequency.
Step S108
In this step, the UE may use the result of the adaptation for one
or more operational tasks and/or send the result to another node
(e.g., another UE, network node, radio network node, core network
node, positioning node, etc.). The result of the adaptation may be
any result (e.g., measurement result, interruption count,
positioning calculation, link adaptation, power control, etc.)
obtained after applying the adaptation.
Examples of the operational tasks:
Informing another node (e.g. network node) that the adaptation has
been/is/will be performed by the UE; Informing another node (e.g.
network node) that the adaptation has been/is/will be performed to
avoid the impact on measurements on specific carrier frequencies
e.g. F 1; Positioning, RRM, MDT, mobility, SON, resource
optimization.
FIG. 6 illustrates another embodiment of a method which can be
performed in a UE such as UE 110. The method illustrated in FIG. 6
includes some rearrangements of steps and elements previously
described (e.g., with respect to FIG. 5). The method may
comprise:
Step S200 (Optional): Performing measurements.
Step S202: Determining a need to report measurements to a radio
network node within a measurement reporting delay.
Step S204: Determining a need to perform a sounding reference
signal, SRS, switching procedure.
Step S206: Extending the measurement reporting delay associated
with reporting the measurements to the radio network node in order
to allow the UE to perform the SRS switching procedure.
Step S208: Reporting the measurements to the radio network node
within the extended measurement reporting delay.
It will be appreciated that one or more of the above steps may be
performed simultaneously and/or in a different order. Also, steps
illustrated in dashed lines are optional and may be omitted in some
embodiments.
The steps will now be described in more detail.
Step S200
In this step, which may be optional, the UE performs one or more
measurements. Generally, the measurements are made on signals
received from one or more radio network nodes such as radio network
node 130.
Step S202
In this step, the UE determines that it needs to report
measurements (e.g., the measurements obtained in step S200) to a
radio network node (e.g., radio network node 130) within a
measurement reporting delay. In some embodiments, the UE may
determine this need to report measurements to the radio network
node based, at least in part, on a measurement configuration and/or
on a measurement reporting configuration which may be received from
the radio network node. The measurement configuration and/or the
measurement reporting configuration may comprise the type or types
of measurements to be performed by the UE and possibly the
reporting delays respectively associated with the measurements.
In some embodiments, the measurement reporting delay may be
understood as the time between an event that will trigger a
measurement report and the point when the UE starts to transmit the
measurement report over the air interface.
Step S204
In this step, the UE determines the need to perform a SRS switching
procedure. In some embodiments, the UE may determine the need to
perform the SRS switching procedure by receiving a request from a
radio network node (e.g., radio network node 130). The request may
be an SRS request carried by a downlink control information
message. In some embodiments, the UE may determine the need to
perform the SRS switching procedure upon the occurrence of one or
more predetermined events (e.g., the expiration of a timer).
Step S206
In this step, the UE extends the measurement reporting delay
associated with reporting the measurements to the radio network
node in order to allow the UE to perform the SRS switching
procedure. In some embodiments, the UE may extend the measurement
reporting delay upon determining the need to perform the SRS
switching procedure after having determined the need to report
measurements to a radio network node within a measurement reporting
delay. In other words, in some embodiments, the UE initially
determines the need to report measurements to the radio network
node within a measurement reporting delay, then determines the need
to perform the SRS switching procedure, and only then proceeds to
extend the measurement reporting delay associated with reporting
the measurements to the radio network node. In some embodiments,
the UE may extend the delay for a predetermined amount of time,
e.g., x subframe or y seconds beyond the normal delay. In some
embodiments, the UE may extend the delay as long as necessary for
the performance and completion of the SRS switching procedure.
Step S208
In this step, the UE reports the measurements to the radio network
node within the extended measurement reporting delay.
The measurements transmitted by the UE to the radio network node
may comprise different types of measurements. For instance, the
measurements may comprise power measurements, quality measurements,
and/or timing measurements. Power measurements may include signal
strength measurements (e.g., RSRP measurements), quality
measurements may include signal quality measurements (e.g., RSRQ
measurements), and timing measurements may include different time
measurements (e.g., Rx-Tx measurements, RTT measurements, RSTD
measurements, TOA measurements, and TDOA measurements). Other
measurements are also possible.
FIG. 7 illustrates an embodiment of a method which can be performed
in a network node such as radio network node 130. The method may
comprise:
Step S300 (Optional): Obtaining information about the UE's ability
to adapt its operations with SRS switching in order to control
(e.g., avoid, reduce, or minimize) the impact of SRS switching on
UL response transmissions.
Step S302: Determining that the UE may need to perform one or more
UL response transmissions on a first carrier frequency (F1) in a
first set of time resources (R1).
Step S204: Determining that the UE may need to perform SRS
switching and transmit, e.g. SRS or PRACH, on at least a second
cell (Cell2) operating on a second carrier frequency (F2).
Step S306: Adaptively controlling the UE's operations with SRS
switching, based on the determined R1.
Step S308: Using the result of the adaptation for one or more
operational tasks and/or sending the result to another node.
It will be appreciated that one or more of the above steps may be
performed simultaneously and/or in a different order. Also, steps
illustrated in dashed lines are optional and may be omitted in some
embodiments.
The steps will now be described in more detail.
Step S300
The network node may obtain the UE's capability based on, e.g.,
receiving a message from the UE or another node, monitoring UE
behavior, etc.
Step S302
In this step, the network node determines that the UE may need to
perform one or more UL response transmissions on a first carrier
frequency (F1) in a first set of time resources (R1).
In some embodiments, the UL response transmissions are to be
transmitted by the UE in response to receiving by the UE one or
more radio signals on the first carrier frequency (F1) in another
set of time resources (R1*). In some embodiments, the determining
of R1 may be based on the determined R1*.
One or more of the methods for determining described for the UE
above may also apply for the network node.
Step S304
In this step the network node determines that the UE may need to
perform SRS switching and transmit, e.g. SRS or PRACH, on at least
a second cell (cell2) operating on a second carrier frequency
(F2).
The determining may be based, e.g., on SRS switching configuration,
on obtained UE's capability previously obtained (see step S300) or
capability to support SRS switching, on a request sent to the UE to
perform SRS switching, etc.
One or more of the methods for determining described for the UE
above may also apply for the network node.
Step S306
In this step, the network node may adaptively control the UE's
operations with SRS switching, based on the determined R1. The
controlling may further comprise sending a message, indication, a
parameter, or a request to the UE.
Examples of adaptation include: Adapting the measurement
configuration and transmitting the adapted measurement
configuration to the UE; Adapting scheduling of signals in the
uplink and/or in the downlink; Changing the sets of or swapping
carrier frequencies of PCell, PSCell and/or SCells of the UE;
Adapting SRS configuration e.g. periodicity and/or bandwidth of the
SRS.
Other examples of adapting have also been described above in
relation to the UE.
Step S308
In this step, the network node may use the result of the adaptation
for one or more operational tasks and/or sending the result to
another node (e.g., another network node or UE).
The operational tasks may be similar to those described with
respect to the UE.
Exemplary Standardization Scenario
In some embodiments, the following sections of 3GPP TS 36.133
v14.1.0 may be modified as follows to enable one or more of the
described embodiments.
======<<<<<<TS
36.133>>>>>======
8.1.2.2.1.1.1.3 Event Triggered Reporting
Reported RSRP, RSRQ, and RS-SINR measurements contained in event
triggered measurement reports shall meet the requirements in
sections 9.1.2.1, 9.1.2.2, 9.1.5.1, and 9.1.17.2.1,
respectively.
The UE shall not send any event triggered measurement reports, as
long as no reporting criteria are fulfilled.
The measurement reporting delay is defined as the time between an
event that will trigger a measurement report and the point when the
UE starts to transmit the measurement report over the air
interface. This requirement assumes that the measurement report is
not delayed by other RRC signalling on the DCCH. This measurement
reporting delay excludes a delay uncertainty resulted when
inserting the measurement report to the TTI of the uplink DCCH. The
delay uncertainty is: 2.times.TTI.sub.DCCH. This measurement
reporting delay excludes a delay which caused by no UL resources
for UE to send the measurement report.
The event triggered measurement reporting delay, measured without
L3 filtering shall be less than T.sub.identify_intra defined in
Clause 8.1.2.2.1.1. When L3 filtering is used or IDC autonomous
denial is configured or the UE is performing reception and/or
transmission for ProSe Direct Discovery and/or ProSe Direct
Communication, or the UE is configured to perform SRS carrier based
switching, an additional delay can be expected.
If a cell which has been detectable at least for the time period
T.sub.identify_intra defined in clause 8.1.2.2.1.1 becomes
undetectable for a period.ltoreq.5 seconds and then the cell
becomes detectable again and triggers an event, the event triggered
measurement reporting delay shall be less than
T.sub.Measurement_Period, Intra provided the timing to that cell
has not changed more than .+-.50 Ts and the L3 filter has not been
used. When L3 filtering is used or IDC autonomous denial is
configured or the UE is performing reception and/or transmission
for ProSe Direct Discovery and/or ProSe Direct Communication,
configured to perform SRS carrier based switching, an additional
delay can be expected.
======<<<<<<TS
36.133>>>>>======
FIG. 8 is a block diagram of an exemplary UE 110, in accordance
with certain embodiments. UE 110 includes one or more of a
transceiver 112, processor 114, and memory 116. In some
embodiments, the transceiver 112 facilitates transmitting wireless
signals to and receiving wireless signals from radio network node
130 (e.g., via transmitter(s) (Tx) 118, receiver(s) (Rx) 120 and
antenna(s) 122). The processor 114 executes instructions to provide
some or all of the functionalities described above as being
provided by UE 110, and the memory 116 stores the instructions
executed by the processor 114. In some embodiments, the processor
114 and the memory 116 form processing circuitry 124.
The processor 114 may include any suitable combination of hardware
to execute instructions and manipulate data to perform some or all
of the described functions of UE 110, such as the functions of UE
110 described above. In some embodiments, the processor 114 may
include, for example, one or more computers, one or more central
processing units (CPUs), one or more microprocessors, one or more
application specific integrated circuits (ASICs), one or more field
programmable gate arrays (FPGAs) and/or other logic.
The memory 116 is generally operable to store instructions, such as
a computer program, software, an application including one or more
of logic, rules, algorithms, code, tables, etc. and/or other
instructions capable of being executed by processor 114. Examples
of memory 116 include computer memory (for example, Random Access
Memory (RAM) or Read Only Memory (ROM)), mass storage media (for
example, a hard disk), removable storage media (for example, a
Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any
other volatile or non-volatile, non-transitory computer-readable
and/or computer-executable memory devices that store information,
data, and/or instructions that may be used by the processor 114 of
UE 110.
Other embodiments of UE 110 may include additional components
beyond those shown in FIG. 8 that may be responsible for providing
certain aspects of the UE's functionalities, including any of the
functionalities described above and/or any additional
functionalities (including any functionality necessary to support
the embodiment(s) described above). As just one example, UE 110 may
include input devices and circuits, output devices, and one or more
synchronization units or circuits, which may be part of the
processor. Input devices include mechanisms for entry of data into
UE 110. For example, input devices may include input mechanisms,
such as a microphone, input elements, a display, etc. Output
devices may include mechanisms for outputting data in audio, video
and/or hard copy format. For example, output devices may include a
speaker, a display, etc.
FIG. 9 is a block diagram of an exemplary radio network node 130,
in accordance with certain embodiments. Radio network node 130 may
include one or more of a transceiver 132, processor 134, memory
136, and network interface 146. In some embodiments, the
transceiver 132 facilitates transmitting wireless signals to and
receiving wireless signals from UE 110 (e.g., via transmitter(s)
(Tx) 138, receiver(s) (Rx) 140, and antenna(s) 142). The processor
134 executes instructions to provide some or all of the
functionalities described above as being provided by a radio
network node 130, the memory 136 stores the instructions executed
by the processor 134. In some embodiments, the processor 134 and
the memory 136 form processing circuitry 144. The network interface
146 communicates signals to backend network components, such as a
gateway, switch, router, Internet, Public Switched Telephone
Network (PSTN), core network nodes or radio network controllers,
etc.
The processor 134 may include any suitable combination of hardware
to execute instructions and manipulate data to perform some or all
of the described functions of radio network node 130, such as those
described above. In some embodiments, the processor 134 may
include, for example, one or more computers, one or more central
processing units (CPUs), one or more microprocessors, one or more
application specific integrated circuits (ASICs), one or more field
programmable gate arrays (FPGAs) and/or other logic.
The memory 136 is generally operable to store instructions, such as
a computer program, software, an application including one or more
of logic, rules, algorithms, code, tables, etc. and/or other
instructions capable of being executed by processor 134. Examples
of memory 136 include computer memory (for example, Random Access
Memory (RAM) or Read Only Memory (ROM)), mass storage media (for
example, a hard disk), removable storage media (for example, a
Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any
other volatile or non-volatile, non-transitory computer-readable
and/or computer-executable memory devices that store
information.
In some embodiments, the network interface 146 is communicatively
coupled to the processor 146 and may refer to any suitable device
operable to receive input for radio network node 130, send output
from radio network node 130, perform suitable processing of the
input or output or both, communicate to other devices, or any
combination of the preceding. The network interface 146 may include
appropriate hardware (e.g., port, modem, network interface card,
etc.) and software, including protocol conversion and data
processing capabilities, to communicate through a network.
Other embodiments of radio network node 130 may include additional
components beyond those shown in FIG. 9 that may be responsible for
providing certain aspects of the radio network node's
functionalities, including any of the functionalities described
above and/or any additional functionalities (including any
functionality necessary to support the embodiment(s) described
above). The various different types of network nodes may include
components having the same physical hardware but configured (e.g.,
via programming) to support different radio access technologies, or
may represent partly or entirely different physical components.
Referring to FIG. 10, in some embodiments, the UE 110 may comprise
a series of modules configured to implement the functionalities of
the UE described above. For instance, in some embodiments, the UE
may comprise a (first) determining module configured to determine a
need to report measurements to a radio network node within a
measurement reporting delay, a (second) determining module
configured to determine a need to perform a sounding reference
signal, SRS, switching procedure, an extending module configured to
extend the measurement reporting delay associated with reporting
the measurements to the radio network node in order to allow the UE
to perform the SRS switching procedure, and a reporting module
configured to report the measurements to the radio network node
within the extended measurement reporting delay.
It will be appreciated that the various modules may be implemented
as combination of hardware and/or software, for instance, the
processor 114, memory 116 and transceiver(s) 112 of UE 110 shown in
FIG. 8. Some embodiments may also include additional modules and/or
sub-modules to support or implement additional and/or optional
functionalities.
Referring to FIG. 11, in some embodiments, the radio network node
130 may comprise a series of modules configured to implement the
functionalities of the radio network node described above. For
instance, in some embodiments, the radio network node may comprise
a (first) determining module configured to determine that a UE may
need to perform one or more uplink, UL, response transmissions on a
first carrier frequency (F1) in a first set of time resources (R1),
a (second) determining module configured to determine that the UE
may need to perform SRS switching and transmit on at least a second
cell (Cell2) operating on a second carrier frequency (F2), a
controlling module configured to adaptively control the operations
of the UE with SRS switching based on the determined R1, and a
processing module configured to use a result of the adaptation for
one or more operational tasks.
It will be appreciated that the various modules may be implemented
as combination of hardware and/or software, for instance, the
processor 134, memory 136 and transceiver(s) 132 of radio network
node 130 shown in FIG. 9. Some embodiments may also include
additional modules and/or sub-modules to support or implement
additional and/or optional functionalities.
Some embodiments may also be represented as a computer program
product comprising a non-transitory machine-readable medium (also
referred to as a computer-readable medium, a processor-readable
medium, or a computer usable medium having a computer readable
program code embodied therein). The machine-readable medium may be
any suitable tangible medium including a magnetic, optical, or
electrical storage medium including a diskette, compact disk read
only memory (CD-ROM), digital versatile disc read only memory
(DVD-ROM) memory device (volatile or non-volatile), or similar
storage mechanism. The machine-readable medium may contain various
sets of instructions, code sequences, configuration information, or
other data, which, when executed, cause a processor to perform
steps in a method according to one or more of the described
embodiments. Those of ordinary skill in the art will appreciate
that other instructions and operations necessary to implement the
described embodiments may also be stored on the machine-readable
medium. Software running from the machine-readable medium may
interface with circuitry to perform the described tasks.
The above-described embodiments are intended to be examples only.
Alterations, modifications and variations may be effected to the
particular embodiments by those of skill in the art without
departing from the scope of the description, which is defined
solely by the claims appended hereto.
ABBREVIATIONS
The present description may comprise one or more of the following
abbreviation:
3GPP Third Generation Partnership Project
ACK Acknowledged
AGC Automatic gain control
AP Access point
BS Base Station
BSC Base station controller
BTS Base transceiver station
CA Carrier Aggregation
CC Component carrier
CGI Cell Global Identifier
CQI Channel Quality information
CRS Cell-specific Reference Signal
CSI Channel State Information
DAS Distributed antenna system
DC Dual connectivity
DCI Downlink Control Information
DL Downlink
DRX Discontinuous Reception
eNB E-UTRAN NodeB or evolved NodeB
ePDCCH enhanced Physical Downlink Control Channel
E-SMLC evolved Serving Mobile Location Center
E-UTRA Evolved UTRA
E-UTRAN Evolved UTRAN
FDD Frequency Division Duplex
FDM Frequency Division Multiplexing
HD-FDD Half duplex FDD
LB T Listen Before Talk
LTE Long-Term Evolution
M2M Machine to Machine
MAC Medium Access Control
MDT Minimization of Drive Tests
MeNB Master eNodeB
MIB Master Information Block
MME Mobility Management Entity
MPDCCH MTC Physical Downlink Control Channel
MSC Mobile Switching Center
MSR Multi-standard Radio
MTC Machine Type Communication
NACK Not acknowledged
NPBCH Narrowband Physical Broadcast Channel
NPDCCH Narrowband Physical Downlink Control Channel
NR New Radio
O&M Operation and Maintenance
OSS Operations Support System
PBCH Physical Broadcast Channel
PCC Primary Component Carrier
PCell Primary Cell
PCFICH Physical Control Format Indicator Channel
PDCCH Physical Downlink Control Channel
PDSCH Physical Downlink Shared Channel
PHICH Physical HARQ indication channel
PRACH Physical Random Access Channel
PRS Positioning Reference Signal
PSCell Primary SCell
PSS Primary Synchronization Signal
PUCCH Physical Uplink Control Channel
PUSCH Physical Uplink Shared Channel
RACH Random Access Channel
RAT Radio Access Technology
RLM Radio Link Management
RRC Radio Resource Control
RRH Remote Radio Head
RRM Radio Resource Management
RRU Remote Radio Unit
RSCP Received Signal Code Power
RSRP Reference Signal Received Power
RSRQ Reference Signal Received Quality
RSSI Received Signal Strength Indicator
RSTD Reference Signal Time Difference
SCC Secondary Component Carrier
SCell Secondary Cell
SeNB Secondary eNodeB
SINR Signal to Interference and Noise Ratio
SNR Signal Noise Ratio
SON Self-organizing Network
SRS Sounding Reference Signal
SSS Secondary synchronization signal
TA Timing Advance
TAG Timing Advance Group
TDD Time Division Duplex
TTI Transmission Time Interval
UE User Equipment
UL Uplink
UMTS Universal Mobile Telecommunication System
UpPTS Uplink Pilot Time Slot
UTRA Universal Terrestrial Radio Access
UTRAN Universal Terrestrial Radio Access Network
* * * * *